Last Tuesday, Rep. Jesse Jackson Jr. left the Mayo Clinic, where the Illinois Democrat was being treated for a second time for bipolar disorder.

Mayo spokesman Nick Hanson told the Associated Press that he did not know where Jackson was going.

Jackson, who was easily elected to a new House term last week, has been on medical leave since June 10. Members of Congress returned to work Tuesday after a lengthy break for the election.

Neither Jackson's congressional spokesman, his publicist nor his father could immediately be reached for comment.

Jackson returned to the hospital in October amid reports that he faced a new federal investigation into potential misuse of his campaign finances. The Chicago Sun-Times first reported the probe, citing anonymous sources.

Jackson, 47, disappeared in June, and it was later revealed that he was being treated at the Mayo Clinic for bipolar disorder and gastrointestinal issues. He returned to his Washington home in September, but went back to the clinic the next month.

His father, the Rev. Jesse Jackson, said then that his son had not yet “regained his balance.”

Jackson was easily elected Nov. 6 to a ninth full term representing his heavily-Democratic Chicago area district, even though he had barely appeared in public since going on medical leave and his only campaigning was a robo-call asking voters for patience. He spent election night at the clinic.

Jackson later issued a statement thanking his supporters and saying he was waiting for his doctors’ OK before he could “continue to be the progressive fighter” they’d known for years.